CARDIFF U. (UK) — A variety of disease-causing parasites are turning up in the bodies of dead otters in the UK.

The most insidious of the parasites, Toxoplasma gondii—which is spread by cat feces—was found in 39.5 percent of otters.

The infection is prevalent across many areas of the UK, with significantly more cases arising in the eastern region. How this affects otters is yet to be determined, researchers say, so further investigation in this area is planned.

In humans the parasite can lead to miscarriage and retinal abnormalities.

Parasitic flatworms—divided into two species Pseudamphistomum truncatum and Metorchis albidus—were found in 18.3 percent of otters. The former flatworm is native to Eastern Europe and infects a range of wild carnivores; both are associated with pathological damage to the otter gall bladder.

Dissections of affected otters revealed gall bladders to be inflamed or thickened. Both parasites can infect any fish eating mammal, including humans.

A species of tick called Ixodes hexagonus was found in nearly a quarter of otters (24.3 percent). Up to 122 ticks per otter were identified. More ticks were found on younger otters than adults.

Scientists reason that this is likely due to younger otters tending to spend more time in the holt (an otter den). As otters are common carriers of this tick, this may have implications for vector-borne diseases, which can infect humans and their companion animals.

“The project’s research on the parasites that infect otters has revealed previously unknown aspects of their distribution and ecology,” says Elizabeth Chadwick, of the Otter Project at Cardiff University.

“Continued work is necessary to help us to better understand their transmission pathways and the impacts that they have on otters, other wildlife, and human health.”